Xerographic toner dispensing apparatus



June 2, 1964 c. R. MAYO ETAL 3,135,433

XEROGRAPHIC TONER DISPENSING APPARATUS Original Filed Nov 19 1955 3 Sheets-Sheet 1 FIG.]

INVENTOR. WILLIAM G. LEWIS CLYDE R MAYO HAROLD E.CLARK ATTORNEY June 2, 1964 c. R. MAYO ETAL 3,1 33

XEROGRAPHIC TONER DISPENSING APPARATUS Original Filed Nov. 19, 1955 3 sheets-sheet 2 on an no 9 wfl mz a M mm w v n no .r MWM MWWNWMWMWMMWMXA\MM x? wnnun qv 2 Q Q w Nv hm WM 3 5 @m m m vm 2., mm mm mm 5 fl m- 3 N QE HAROLD E.CLARK I WW W June 2, 1964 MAYQETAL 3,135,433

XEROGRAPHIC TONER DISPENSING APPARATUS FIGS INVEN TOR. WILLIAM G. LEWIS CLYDE R. MAYO HAROLD E. CLARK ATTORNEY United States Patent 3,135,433 XERGGRAPHEQ TONER DESPENSING APPARATUS (Ilyde R. Mayo and William G. Lewis, Rochester, and Harold E, Clark, Penfield, N.Y., assignors to Xerox gorporation, Rochester, N.Y., a corporation of New Original application Not-19, 1953, Ser. No. assess.

'drum having a xerographic surface thereon, a given portion of which is successively electrostatically charged, exposed, developed by a mixture of carrier and toner particles, and brought into contact with a transfer sheetor paper, and it has for its purpose to atfordan efiicient and successful method and structure for automatically controlling the amountoftoner in the mixture employed for developing the image on the xerographic plate and maintaining a more nearly constant relationship between the carrier and toner particles in the mixture.

According to known practices in the art, a xerographic ice method can be performed, and showing a preferred arrangement constructed in accordance with the invention; FIG. 2 is an enlarged detail sectional view of the toner dispenser constituting the present invention; and I PEG. 3 is a bottom plan View of the parts appearing in FIG. 2."

Referring more particularly to the drawings in which i like reference numerals refer tothe same parts throughout the several views, 1 designates a drum-which is rotated continuously at a given speed, and 2 is a microfilm that p is fed from a supporting reel 3 to a receiving reel 4- by suitable drive mechanism which effects travel of the film at a rate in conformity with the speed of the drum 1 and degree of magnification of the film onto the drum. 5

designates projection mechanism which directs light throughthe film and projects the image from the film through the optical system which magnifies the image, barrel 6, and slit 7 on to a portion of the insulating photoconduc tive surface which covers the periphery of the drum 1.

The drum 1 travels in a clockwise direction and during the'cour'se of its rotation, at given portion of the photoimage is developed by cascading over an electrostatic image on a xerographic surface a developer material consisting of a mixture of carrier particles or beads, and

finely ground toner particles or powder consisting of a finely ground mass of black or other suitable pigment and a thermo-plastic material, the carrier and toner particles being so selected that when mixed together, frictiongenerated charges are imposed thereon, positive charges on one group of particles and negative charges on the other group of particles. In the course of continuous operation of such an apparatus, the'proportion of toner particles in the mixture in relation to the carrier particles becomes less and it is necessary to replenish the toner in order' to maintain a constant balance between the tonerand carrier and to retain the effectiveness of the developer, and this invention has to do with a method and apparatus forcirculating and continuously supplying developer to the xerographic surface on a rotating drum and for maintaining a uniform degree of concentration of toner particles in relation to the carrier particles in the developer mixture.

The invention has for a further purpose to afford structure which continuously circulates an excess of developer mixture and removes excess toner from the mixture so that when the developer mixture passes through a developer chamber in contact with a xerographic image on the rotating drum, a more uniform degree of concentration of the toner in the mixture is assured.

Still another object of the invention is to provide apparatus for continuously circulating a developer mixture of conductive or xerographic surface thereon is first subjected to the operation of suitable cleaning brushes 8 that remove any adhering developer material, following which the previously cleaned portion of the xerographic surface is illuminated by. a fluorescent discharge lamp 9 which insures removal of any electrostatic chargesremaining on the surface of the drum induced by the cleaning brushes 8 or-otherwise. After leaving the discharge lamp 9, the portion of the surface of the drum thereunder is next subjected to a charging grid 11 which imposes the required electrostatic charge on the xerographic surface which is next exposed to a light image through the slit 7, and then passes under an electrometer 12 for determining the potential of the charge on the drum, following which the electrostatic image produced by exposure through the slit carrier and toner particles through a developer chamber and cascading the developermixture over a xerographic image surface on the drum, and at the same time continuously feeding a supply offresh toner particles to the. mixture and thus maintaining a uniform relationship between the volume of carrier particles and of toner particles in the developer rm'xture. I

To these and other ends, the invention consists in the illustrating a continuously operable machine on which the c '7 passes through a developer chamber13 consisting of a housing located adjacent to the surface of the drum and extending from side to side thereof, forming a closed and substantially sealed chamber for a purpose that will appear presently.

Connected with the upper portion of the developer chamber 13 is a hopper 14 from which the developer mixture, consisting of carrier particles or beads and finely ground toner particles, is conducted into the developer chamber 13, the hopper 14 being in communication with the developerchamber 13 so that the developer mixture 0' is fed by gravity into the developer chamber and cascades 5 downwardly over the surface of the drum. Toward the lower end of the developer chambenthere is provided a baifle 15 which deflects the developer mixture into a mixing drum 16, the latter having an opening 17 at its upper end which is in communication with the lower portion of thedeveloper chamber.

The mixing drum 16 is preferably inclined to a horizontal plane at approximately the angle shown in FIG. 1

and is provided with an agitator including blades or paddles 18 which are rotated by any suitable means, effecting thorough mixing of the carrier and toner particles and downward flow of the mixture through the drum, and into a conduit 19 leading from an opening at the upper portion of the lower end of the drum downwardly to a vertical housing 21 within which is located a vertically traveling conveyor 22 provided with suitable buckets 23 that carry the developer mixture upwardly within the housing 21 and discharge it at its upper end into an outlet 24 that communicates at its lower end with the upper portion of the aforementioned hopper 14. The conveyor 22 is operated by any suitable drive mechanism and in this fashion, a continuous circulation of developer 25 designates a toner supply hopper connected by a conduit 26 with the mixing drum 16, and mounted above the toner supply hopper 25 and suitably supported thereon is a housing 27 that supports a removable toner-container or bottle 28, the latter being threaded to receive a cover that includes plates 29 and 31, while 32 designates a shutter or valve rotatably mounted between the plates 29 and 31, and having openings 33 adapted to register with corresponding openings in the plates 29 and 31 when positioned by means of a handle 34 to permit toner to be discharged from the container.

Mounted in a bearing 35 carried by the cover is an arbor 36 provided With an upwardly extending inclined portion 3'7 and vertical portion 38 arranged adjacent to the wall of the container and acting when the arbor 36 is rotated to sweep the toner contents away from the sides of the container, while 39 designates an arm mounted on arbor 36 immediately above plate 29 and valve 32, and operating to agitate the material at the bottom of the container continuously and sweep it into the openings of the cover when the valve is open. The arbor 36 at its lower end carries a right-angled arm 41 that is engaged and turned by a pin 42 extending upwardly from and carried by an arm 43 mounted on the vertical shaft 44 that rotates in bearings in the supporting plates 45 and 46 secured within the toner housing 27, while 47 designates a sleeve fixed to the shaft 44 and provided with agitating blades 48 that constantly stir the powder in toner housing 27, the shaft 44 being provided at its lower end with a sprocket 49 that is driven by a chain from pinion 5t suitably operated from the electric motor 52, the speed of which may be varied to increase or decrease the amount of toner supplied from the dispenser as conditions may require from time to time. 51 designate stirring blades mounted on shaft 36 and operating to loosen and mix the toner as it is discharged from the container 28.

The speed of motor 52 and dispensing rate of the toner may be varied depending in part on the action of the dust collector, which in some measure affects the degree of concentration of the toner in the mixture, in conjunction with or independently of the toner dispenser, as will be described more fully hereinafter. The toner is discharged from housing 27 through openings 53 in the bottom plate 46 of the toner housing, and the lower agitator 48 is provided with a horizontal portion 54 at its bottom that rides over the top surface of the bottom plate 46 to continuously push toner at the bottom of the housing into the openings 53, while 55 designate Wire fingers of suitable form carried by the supporting plate 56 and movable into the openings 53 in the bottom plate 46 of the toner housing as the supporting plate 56 rotates with shaft 44 on which plate 56 is mounted. The fingers 55 can swing into and out of the openings 53 to agitate and loosen any toner that may adhere in the openings and cause it to travel freely downwardly into hopper 25 whence it passes through the chute 26 into the mixing drum l6.

The container 28 with the cover including plates 29 and 31 threaded thereon is removable from toner housing 27 and when in operative position rests upon the upper edge of the latter. When the supply of toner is exhausted, the container or bottle 28 and cover are lifted off from housing 27 after first closing the valve 32, and the cover is then removed from the container by unscrewing. Following this, the cover carrying stirrer 33,

4- arbor 36, and arm 41, may be threaded onto another container of toner and again placed on top of the housing 27 in inverted position as shown, after which the valve 32 is opened and the toner supply mechanism is again ready for operation.

While the invention has been described with reference to the particular structure shown herein, it is not restricted to the details disclosed, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements and the scope of the following claims.

This application is a division of our copending application Serial No. 393,058, filed November 19, 1953, now abandoned.

What is claimed is:

1. A toner dispenser for a xerographic reproducing apparatus, said toner dispenser including a toner housing having a bottom plate containing a plurality of apertures therein, a shaft journaled in said housing, a supporting plate secured to said shaft beneath said bottom plate and having a discharge port adapted upon rotation of said supporting plate to be brought into alignment with said apertures in said bottom plate, flexible fingers secured to said supporting plate and extending through said discharge port into interference relation with said bottom plate and adapted to project into said apertures when in alignment therewith to loosen toner therein, agitator and scraper means in said housing connected to said shaft for rotation therewith to carry toner into said apertures in said bottom plate, a cover releasably secured to the top of said housing, said cover containing valve means, an inverted toner container releasably secured to said cover, second agitator means journaled in said cover and extending at one end into said inverted toner container and at its other end into said housing, and coupling means secured to said shaft and releasably secured to said second agitator means whereby said second agitator means is rotated by said shaft.

2. A toner dispenser for a xerographic reproducing apparatus, said toner dispenser including a toner housing having a bottom plate containing a plurality of apertures therein, a shaft journaled in said housing, a supporting plate secured to said shaft beneath said bottom plate and having a discharge port adapted upon rotation of said supporting plate to be brought sequentially into alignment with said apertures of said bottom plate, flexible fingers secured to said supporting plate and extending through said discharge port into interference relation with said bottom plate and adapted to project into said apertures to loosen toner therein, agitator and scraper means in said housing connected to said shaft for rotation therewith to carry toner into said apertures in said bottom plate and positioned with respect to said discharge port to sequentially cover each of said apertures as said discharge port sequentially comes into alignment with each of said apertures as the supporting plate is rotated, a cover releasably secured to the top of said housing, said cover containing valve means, an inverted toner container releasably secured to said cover, second agitator means journaled in said cover and extending at one end into said inverted toner container and at its other end into said housing, and coupling means secured to said shaft and releasably secured to said second agitator means whereby said second agitator means is rotated by said shaft.

3. A toner dispenser for a xerographic reproducing apparatus, said toner dispenser including a toner housing having a bottom plate containing a plurality of apertures therein, a shaft journaled in said housing, a supporting plate secured to said shaft beneath said bottom plate and having a discharge port adapted upon rotation of said supporting plate to be brought into alignment with said apertures of said bottom plate, flexible fingers secured to said supporting plate and extending through said discharge port into interference relation with said bottom plate and adapted to project into said apertures to 5 V loosen toner therein, agitator and scraper means in said housing connected to said shaft for rotation therewith to carry toner into said apertures in said bottom plate, a cover releasably secured to the top of said housing, said cover including a first plate, a second plate secured in spaced relation to said first plate, and a valve rotatably mounted between said first plate and said second plate,

an inverted toner container releasably secured to said cover, second agitator means journaled in said cover and extending at one end into said inverted toner container and at its other endinto said housing, and coupling means secured to said shaft and releasably secured to said second agitator means whereby said second agitator means is rotated by said shaft.

References Cited in the file of this patent UNITED STATES PATENTS Binley Feb. 7, Powter Feb. 19, Sundstrom Nov. 12, Hess Dec. 20, Vermillion Nov. 25, Broden Sept. 12, Hancock et al. Apr. 10, Cordis Mar. 4, Crumrine et a1. Feb. 19, Crumrine et al. Sept. 16, 

1. A TONER DISPENSER FOR A XEROGRAPHIC REPRODUCING APPARATUS, SAID TONER DISPENSER INCLUDING A TONER HOUSING HAVING A BOTTOM PLATE CONTAINING A PLURALITY OF APERTURES THEREIN, A SHAFT JOURNALED IN SAID HOUSING, A SUPPORTING PLATE SECURED TO SAID SHAFT BENEATH SAID BOTTOM PLATE AND HAVING A DISCHARGE PORT ADAPTED UPON ROTATION OF SAID SUPPORTING PLATE TO BE BROUGHT INTO ALIGNMENT WITH SAID APERTURES IN SAID BOTTOM PLATE, FLEXIBLE FINGERS SECURED TO SAID SUPPORTING PLATE AND EXTENDING THROUGH SAID DISCHARGE PORT INTO INTERFERENCE RELATION WITH SAID BOTTOM PLATE AND ADAPTED TO PROJECT INTO SAID APERTURES WHEN IN ALIGNMENT THEREWITH TO LOOSEN TONER THEREIN, AGITATOR AND SCRAPER MEANS IN SAID HOUSING CONNECTED TO SAID SHAFT FOR ROTATION THEREWITH TO CARRY TONER INTO SAID APERTURES IN SAID BOTTOM PLATE, A COVER RELEASABLY SECURED TO THE TOP OF SAID HOUSING, SAID COVER CONTAINING VALVE MEANS, AN INVERTED TONER CONTAINER RELEASABLY SECURED TO SAID COVER, SECOND AGITATOR MEANS JOURNALED IN SAID COVER AND EXTENDING AT ONE END INTO SAID INVERTED TONER CONTAINER AND AT ITS OTHER END INTO SAID HOUSING, AND COUPLING MEANS SECURED TO SAID SHAFT AND RELEASABLY SECURED TO SAID SECOND AGITATOR MEANS WHEREBY SAID SECOND AGITATOR MEANS IS ROTATED BY SAID SHAFT. 